Countermeasure device for a mobile tracking device

ABSTRACT

A countermeasure device for directing a mobile tracking device away from an asset is provided. The countermeasure device includes a continuous wave laser source whose output is directed at a seeker head of the mobile tracking device. The countermeasure device causes the generation of localized sources within the mobile tracking device and confuses the mobile tracking device as to the true location of the asset.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

The invention described herein was made in the performance of officialduties by employees of the Department of the Navy and may bemanufactured, used and licensed by or for the United States Governmentfor any governmental purpose without payment of any royalties thereon.

BACKGROUND OF THE INVENTION

The present invention relates generally to a countermeasure device whichcauses a mobile tracking device to not approach closer to an asset, andmore particularly, to a countermeasure device which directs the mobiletracking device away from the asset or disables the tracking device.

Presently, a multitude of mobile tracking devices are known whichidentify an asset and attempt to move closer to the asset andpotentially contact the asset. Examples of mobile tracking devicesinclude infrared based mobile tracking devices which examine theinfrared energy which is emitted by the asset and detected by the mobiletracking device. These infrared mobile tracking devices alter theirdirection of travel to track the highest infrared energy being detectedwithin their field of view. Such mobile tracking devices may rely on anon-imaging detection system or an imaging detection system.

There are several countermeasures available to misdirect a mobileinfrared tracking device away from an asset. One exemplarycountermeasure device is infrared hot bodies which appear brighter tothe mobile infrared tracking device than the asset. These infrared hotbodies may be expelled by the asset. The mobile tracking device detectsthe brighter infrared hot bodies and follows the hot bodies as theybecome further spaced apart from the asset; thereby directing the mobileinfrared tracking device away from the asset. Exemplary infrared hotbodies include flares.

Another type of countermeasure device is a laser jamming device. Laserjamming devices are most effective against non-imaging mobile trackingdevices. Laser jamming devices direct a pulsed or modulated laser signalat a detection system of the mobile tracking device. The pulsed ormodulated laser signal is tailored to the specific characteristics ofthe mobile tracking device. An example of one laser jammer which iscapable of jamming multiple types of tracking devices by varying aperiod of the modulated laser signal is disclosed in U.S. Pat. No.6,359,710. Another exemplary laser jamming system is the AN/AAQ-24Nemesis DIRCM system provided by Northrup Grumman Corporation located inLos Angeles, Calif.

SUMMARY OF THE INVENTION

In an exemplary embodiment of the present disclosure, a countermeasuredevice is disclosed. In another exemplary embodiment, a method ofinteracting with a mobile tracking device is disclosed.

In yet another exemplary embodiment of the present disclosure, anapparatus for interacting with a mobile tracking device is provided. Theapparatus comprising: a plurality of sensor modules which monitor theenvironment; a first controller portion operatively connected to theplurality of sensor modules, the first controller portion determining apresence of the mobile tracking device in the environment based oninformation collected by the plurality of sensor modules and a currentlocation of the mobile tracking device; and a countermeasure system. Thecountermeasure system including a second controller portion whichreceives the current location of the mobile tracking device from thefirst controller portion, orients a tracking system of thecountermeasure system based on the current location of the mobiletracking device, detects the mobile tracking device, updates thelocation of the mobile tracking device, activates a continuous wavelaser, and directs a continuous beam of optical energy at the mobiletracking device.

In a further exemplary embodiment, a method for keeping a mobiletracking device away from an asset is provided. The mobile trackingdevice having a seeker head which is directed at an asset due to theinfrared energy radiated by the asset. The method comprising the stepsof: directing an output of a continuous wave laser at the seeker headalong a first direction of travel of the mobile tracking device, theoutput of the continuous wave laser being infrared energy; andpropagating the infrared energy from the continuous wave laser into theseeker head of the mobile tracking device to generate at least onelocalized source within the mobile tracking device and within a field ofview of the mobile tracking device which indicates a second direction oftravel for the mobile tracking device.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of thisinvention will become more readily appreciated as the same become betterunderstood by reference to the following detailed description when takenin conjunction with the accompanying drawings.

FIG. 1 illustrates a representative view of a countermeasure device andassociated asset;

FIG. 2 is a view of a representative asset;

FIG. 2A illustrates the representative asset of FIG. 2 with a mobiletracking device approaching the representative asset along a firstdirection and optical energy from the countermeasure device beingdirected at the mobile tracking device;

FIG. 2B illustrates the mobile tracking device changing its direction oftravel to a second direction due to the optical energy directed from thecountermeasure device at the mobile tracking device;

FIG. 2C illustrates the mobile tracking device changing its direction oftravel to a third direction due to the optical energy directed from thecountermeasure device at the mobile tracking device;

FIG. 2D illustrates the mobile tracking device changing its direction oftravel to a fourth direction due to the optical energy directed from thecountermeasure device at the mobile tracking device;

FIG. 3 illustrates an exemplary mobile tracking device;

FIG. 4 illustrates an exemplary laser source;

FIG. 5 illustrates a perspective view of a countermeasure device whereinportions of the housing are shown in phantom;

FIG. 6 illustrates a first arrangement of components of the portablecutting device;

FIG. 7 illustrates a second arrangement of components of the portablecutting device;

FIG. 8 illustrates a processing sequence for charging the battery sourceof the countermeasure device;

FIG. 9 illustrates a representative view of a countermeasure device andassociated asset;

FIGS. 10A and 10B illustrate a processing sequence for engaging a mobiletracking device;

FIG. 11 illustrates a representative asset being tracked by arepresentative mobile tracking device;

FIGS. 12 and 13 represent the response characteristics of a mobiletracking device following an asset; and

FIGS. 14 and 15 represent the response characteristics of a mobiletracking device following an asset and being subsequently illuminated bya countermeasure device; and

FIG. 16 illustrates a method of countering a mobile tracking device witha countermeasure device.

Corresponding reference characters indicate corresponding partsthroughout the several views. Although the drawings representembodiments of various features and components according to the presentdisclosure, the drawings are not necessarily to scale and certainfeatures may be exaggerated in order to better illustrate and explainthe present disclosure. The exemplification set out herein illustratesembodiments of the invention, and such exemplifications are not to beconstrued as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF THE DRAWINGS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings, which are described below. The embodiments disclosed beloware not intended to be exhaustive or limit the invention to the preciseform disclosed in the following detailed description. Rather, theembodiments are chosen and described so that others skilled in the artmay utilize their teachings. It will be understood that no limitation ofthe scope of the invention is thereby intended. The invention includesany alterations and further modifications in the illustrated devices anddescribed methods and further applications of the principles of theinvention which would normally occur to one skilled in the art to whichthe invention relates.

The present disclosure is directed to countermeasure devices which areimplemented to protect aircraft, such as commercial airlines andmilitary aircraft. However, the principles discussed herein areapplicable to other types of assets. Exemplary assets include moveableassets, such as aircraft, ships, buses, or trucks, or land based assets,such as an airport, factory, building, or facility.

Referring to FIG. 1, a countermeasure device 100 is shown.Countermeasure device 100 is coupled to an asset 102. For purposes ofdiscussion, asset 102 is considered to be an airplane, such as theairplane designated 102 in FIG. 2. However, the present disclosure iscontemplated for use with a multitude of different assets. Airplane 102includes a body or fuselage 104, a pair of main wings 105, tail wings106, and a plurality of propulsion devices 108. Exemplary propulsiondevices include jet engines, internal combustion engines with associatedpropellers, and any other suitable engine arrangement.

Referring to FIG. 3, components of a mobile tracking device 110 areshown. Mobile tracking device 110 includes a propulsion system 112 whichprovides power to propel mobile tracking device 110. Exemplarypropulsion systems include solid fuel rockets, engines, and any othersuitable devices for providing power to mobile tracking device 110.Mobile tracking device 110 also includes a guidance system 114 whichcontrols the direction of travel of mobile tracking device 110.Exemplary guidance system components include wings for an airbornemobile tracking device 110, a rudder for a marine mobile tracking device110, and ground engaging members for a land based mobile tracking device110. The guidance system 114 steers mobile tracking device 110 to changea direction of travel of mobile tracking device 110. Exemplary airbornetracking devices include rockets, airplanes, and other flying devices.Exemplary marine tracking devices include boats (see FIG. 11),submersible devices, and other marine devices. Exemplary land basedtracking devices include wheeled devices, tracked devices, and othersuitable land based devices.

Mobile tracking device 110 includes a controller 116 which controls theoperation of propulsion system 112 and guidance system 114. Mobiletracking device 110 also includes a gimbaled seeker head 115 which isable to move independent of the remainder of mobile tracking device 110.Seeker head 115 supports controller 116, a detector 118, telescope 120,a reticule 122, and optics 124.

In operation, electromagnetic radiation 126 from the environment entersan optical window 128 of mobile tracking device 110. Optical window 128may be a dome. Optical window 128 may be selected to only passelectromagnetic radiation 126 within a certain wavelength band. Forinstance, in the case of an infrared mobile tracking device 110, opticalwindow 128 may only pass electromagnetic radiation 126 within theinfrared spectrum or a portion of the infrared spectrum. In otherembodiments, a separate filter 125 is included somewhere within theoptical setup of mobile tracking device 110 to limit the range ofwavelengths of electromagnetic radiation 126 passed on to detector 118.Filter 125 is shown between optical window 128 and telescope 120.However, filter 125 may be positioned anywhere between optical window128 and detector 118.

The electromagnetic radiation 126 is received by telescope 120.Telescope 120 includes a primary mirror 121 which focuses theelectromagnetic radiation 126 towards a secondary mirror 123. Secondarymirror 123 in turn focuses the electromagnetic radiation 126 towardsreticule 122. Reticule 122 spins to provide a modulated signal of theelectromagnetic radiation. Optics 124 receives and focus the modulatedsignal of the electromagnetic radiation 126 passing through reticule 122onto detector 118 which is a non-imaging detector.

Controller 116 receives input from detector 118 which is used bycontroller 116 to determine the location the brightest object in theenvironment, typically asset 102. The modulated signal allows controller116 to discriminate between background electromagnetic radiation and theradiation of asset 102, as well as, determine the location of asset 102relative to a direction of travel of mobile tracking device 110. Basedon this input from detector 118, controller 116 determines a desireddirection of travel for mobile tracking device 110 which corresponds totracking device 110 heading towards asset 102. Seeker head 115 isadjusted to center the brightest object in the environment so thatseeker head 115 is pointed directly at the brightest object. Controller116 provides this adjustment of seeker head 115 (from its intendedorientation in line with the direction of travel of mobile trackingdevice 110) to guidance system 114 as error signal 129. Guidance system114 uses this error signal 129 to alter the direction of travel ofmobile tracking device 110. Over time, if mobile tracking device 110 istracking asset 102 mobile tracking device 110 will be pointed at asset102 and seeker head 115 generally produces a small error signal which isindicative of mobile tracking device 110 being aligned to interceptasset 102.

In the embodiment illustrated in FIG. 3, mobile tracking device 110includes a spinning reticule 122. In another embodiment, mobile trackingdevice 110 does not include reticule 122 but rather secondary mirror 123is tilted and telescope 120 is spun to produce a signal for controller116. In one embodiment, detector 118 is an imaging detector andcontroller 116 processes the images from detector 118 to determine thelocation of asset 102.

Returning to FIG. 2, airplane 102 includes warning/cuing system 130which detects when a mobile tracking device 110 has been launched and/oris tracking airplane 102. Warning/cuing system 130 includes sensormodules 131 which monitor the environment around airplane 102.Illustratively, four sensor modules 131A-D are shown. Depending on theasset 102 being protected, fewer or additional sensor modules 131 may beused. In one embodiment, sensor modules 131 include focal plane arraysensors with wide field of views that continuously survey theenvironment for mobile tracking devices 110. In one embodiment,warning/cuing system 130 looks for a characteristic signal thatindicates the launch of an airborne mobile tracking device 110. In thecase of airborne mobile tracking device 110, the mobile tracking device110 has a characteristic infrared and ultraviolet signature whichwarning/cuing system 130 recognizes as an airborne mobile trackingdevice 110.

Exemplary warning/cuing systems include Model No. AAR-54 EWS availablefrom Northrup Grumman Corporation located in Los Angeles, Calif. Asexplained herein, warning/cuing system 130 communicates withcountermeasure device 100. Countermeasure device 100, in turn, providesoptical energy from a continuous wave laser to redirect mobile trackingdevice 110 from tracking the path of asset 102 or to disable mobiletracking device 110. In one embodiment, warning/cuing system 130 isprovided as part of countermeasure device 100 instead of as a separatecomponent of airplane 102.

Airplane 102 further includes a fire control system 140. Fire controlsystem 140 interprets information provided by warning/cuing system 130and provides a user interface 142 through which the operator of asset102 activates countermeasure device 100. In one embodiment, userinterface 142 includes a user input 143 to enable countermeasure device100 and a user input 145 to permit countermeasure device 100 to fire. Inone embodiment, countermeasure device 100 is automatically activatedwhen asset 102 is moving. Exemplary inputs include switches, buttons,and other suitable types of user inputs.

Returning to FIG. 1, countermeasure device 100 is represented.Countermeasure device 100 includes an optical transmitter system 150, apower system 152, a system controller 154, and a cooling system 156.Each of optical transmitter system 150, power system 152, and coolingsystem 156 are coupled to system controller 154. System controller 154receives input from and provides instructions to each of opticaltransmitter system 150, power system 152, and cooling system 156 tocontrol the operation of countermeasure device 100. As explained herein,in one embodiment, countermeasure device 100 is housed in aself-contained pod which may be coupled to asset 102.

Optical transmitter system 150 includes a laser source module 160 and abeam control module 162. Laser source module 160 includes a high voltagepower supply 164 which receives power from power system 152. Highvoltage power supply 164 drives a continuous wave laser 166. In oneembodiment, continuous wave laser 166 is a continuous wave fiber laser.In one embodiment, continuous wave laser 166 is a continuous waveYtterbium single mode fiber laser. Details regarding an exemplarycontinuous wave laser 166 are provided in U.S. patent application Ser.No. 11/973,437, filed Oct. 9, 2007 and issued as U.S. Pat. No. 7,593,435on Sep. 22, 2009, titled POWERFUL FIBER LASER SYSTEM, assigned to IPGPhotonics Corporation, the disclosure of which is expressly incorporatedby reference herein. Details regarding an exemplary continuous wavelaser 166 are provided in U.S. patent application Ser. No. 11/611,247,filed Dec. 15, 2006 subsequently abandoned, titled FIBER LASER WITHLARGE MODE AREA FIBER, assigned to IPG Photonics Corporation, thedisclosure of which is expressly incorporated by reference herein. Inone embodiment, continuous wave laser 166 is a solid state laser. Otherexemplary continuous wave lasers include a 2.0 micrometer (μm) ThuliumFiber Laser (1.96-2.2 (μm) Thulium laser) having an output power ofabout at least 1 kW and a 1.0 μm, 800 Watt Direct Diode. An exemplaryThulium fiber laser is disclosed in U.S. Pat. No. 6,801,550, thedisclosure of which is expressly incorporated by reference herein.

Referring to FIG. 4, an exemplary configuration of continuous wave laser166 is shown. Continuous wave laser 166 includes a plurality ofindividual modules 300 each of which provide a single mode 1.07 μmoutput beam. The output of each of modules 300 is combined togetherthrough a module combiner 302 which brings the energy together in asingle beam. This combined beam is coupled to an optical conduit 170through a quartz coupler 304. Although three laser modules 300 areillustrated, any number of laser modules 300 may be included.

The components of a given laser module 300 are also shown in FIG. 4. Thelaser module 300 includes a plurality of diode lasers 310 each of whichare coupled into a respective Ytterbium fiber 312. The output of theYtterbium fibers 312 are combined through a fiber combiner 314 whichbrings the energy together. This energy is fed through a coupler 315into an Ytterbium fiber optic gain medium 316 which produces therefrom asingle mode 1.07 μm output beam. Although three diode laser sets 310 areillustrated any number of diode laser sets 310 may be included.

In one embodiment, the power of continuous wave laser 166 is about 3kilowatts (kW). In one embodiment, the power level of continuous wavelaser 166 is about 5 kW. In one embodiment, the power level ofcontinuous wave laser 166 is about 10 kW. In one embodiment, the powerlevel of continuous wave laser 166 is about 20 kW. In one embodiment,the power level of continuous wave laser 166 is about 50 kW. In oneembodiment, the power level of continuous wave laser 166 is betweenabout 3 kW and 20 kW. In one embodiment, the power level of continuouswave laser 166 is at least 3 kW.

Returning to FIG. 1, the optical energy produced by continuous wavelaser 166 is communicated to beam control module 162 through opticalconduit 170. An exemplary optical conduit 170 is a fiber optic cable.

Beam control module 162 includes a beam expander 172 and a positioningsystem 174. Beam expander 172 receives the optical energy from opticalconduit 170 and provides a generally collimated beam 176 of opticalenergy which exits countermeasure device 100. An exemplary beam expanderis a Cassegrain telescope. Optical energy from optical conduit 170 isprovided at a focus of the Cassegrain telescope which then generallycollimates this optical energy to produce the expanded beam of opticalenergy 176. In one embodiment, a path length of beam expander 172 may beautomatically adjusted by system controller 154 to change output beam176 from a generally collimated beam of optical energy to a focused beamof optical energy. In this case, beam expander 172 may serve both as abeam expander (collimator) and focusing optics. In one embodiment, beamcontrol module 162 also includes separate focusing optics 177 whichfocus the output beam 176 at a given distance from countermeasure device100.

Positioning system 174 alters the direction in which collimated beam 176is directed. Referring to FIG. 5, an exemplary configuration ofcountermeasure device 100 is shown. Countermeasure device 100 includes ahousing 180 which houses system controller 154, power system 152,cooling system 156 and laser source module 160 of optical transmittersystem 150. Provided on a lower side of housing 180 is positioningsystem 174. Positioning systems 174 includes a housing 182 coupled tohousing 180 and a rotatable head 184 which is rotatable in directions186 and 188. In one embodiment, the rotatable head 184 has a pointingaccuracy of up to 25 micro-radians. Rotatable head 184 includes anoptical window 190 through which output beam 176 is directed. Outputbeam 176 is generally a directed beam and is not radiated in alldirections. In one embodiment, positioning system 174 also includes atleast one reflector 179 which may be controlled to alter the directionoutput beam 176 in directions 187 and 189. The reflector 179 may betilted to alter the elevation of collimated beam 176 by positioningsystem 174.

Housing 180, in the illustrated embodiment, is a pod which is detectablycoupled to airplane 102 (see FIG. 2). Referring to FIG. 5, housing 180includes a set of couplers 181 which cooperate with couplers 183 onasset to couple housing 180 to airplane 102. In one embodiment, housing180 is coupled to airplane 102 by any suitable conventional mechanismwhich permits housing 180 to be later detached from airplane 102. Anexemplary system is the coupling system used with the AN/AAQ-28(V)LITENING targeting pod commercially available from Northrop GrummanCorporation located in Los Angeles, Calif.

Returning to FIG. 1, power system 152 includes a power source 200. Inone embodiment, power source 200 is a plurality of batteries. Thebatteries may be rechargable batteries. Exemplary rechargeable batteriesinclude lithium-ion batteries and lithium polymer batteries. Exemplarylithium-ion batteries include commercially available cells, such asthose available from A123 Systems located in Watertown, Mass. In oneembodiment, a plurality of lithium-ion cells are assembled into abattery pack 202 (see FIG. 5). In one embodiment, these cells have anominal amp-hour rating of 2.3 Ah and a nominal load voltage of 3.3DCV/cell. Based thereon, battery pack 202 should be able to deliver 52.8Vat 2.3 amps for 1 hour. Under high load (10 C (10×5×2.3 or 115 Amps))the voltage will “squat” to approximately 2.8 volts/cell. At this levelthe battery pack 202 could deliver 45 Vat 115 amps (or 5 kW) for 6 min.Under severe load (20 C (20×5*2.3) or 230 amps)) the voltage would squatto approximately 2.5 volts. At this level the battery pack 202 coulddeliver 40 V at 230 amps (or 9 kW) for about a half minute. In oneembodiment, battery pack 202 provides 28 VDC power for countermeasuredevice 100.

The use of battery pack 202 allows high power to be provided to lasersource module 160 without causing a large power spike requirement in thepower system of asset 102. In essence, battery pack 202 acts as acapacitor for laser source module 160.

In one embodiment, continuous wave laser 166 is a three kilowattYterrbium single mode fiber laser such as ones commercially availablefrom IPG Photonics located at IPG Photonics Corporation, 50 Old WebsterRoad Oxford, Mass. 01540 USA and power supply 152 provides about 28 VDC.In general, commercial laser sources from IPG Photonics include anAC-to-DC converter to convert power from an AC source to DC power forcontinuous wave laser 166. Since power supply 152 already provides DCpower, when a commercial laser source is being used for continuous wavelaser 166 the AC-to-DC converter is removed and replaced with a DCdriving circuit 320 (see FIGS. 6 and 7) which corresponds high voltagepower supply 164. DC driving circuit 320 provides power from powersupply 152 to continuous wave laser 166 and regulates the power levelprovided.

Referring to either FIG. 6 or FIG. 7, continuous wave laser 166 isrepresented. Continuous wave laser 166, as explained in connection withFIG. 4, includes a laser pump system 322 which includes a plurality oflaser diodes 310. Laser diodes 310 provide the pump energy for thelasing medium 316 of continuous wave laser 166. The lasing medium 316 isprovided as part of a fiber optical cable. The output of the lasingmedium 316 is provided to optical conduit 170.

In FIG. 6, power supply 152 is coupled to laser diodes 183 through DCdriving circuit 320 which includes a single voltage regulator 326 thatpowers laser diodes 310. In FIG. 7, power supply 152 is coupled to laserdiodes 310 through DC driving circuit 320 which includes a plurality ofcurrent regulators 328. Each current regulator 328 provides the power toone of the modules 300 (see FIG. 4) to provide power to the diodes ofthat module 300.

Referring to either FIG. 6 or FIG. 7, power supply 152 may be chargedwith a battery charger 330 coupled to a prime power source 332. Batterycharger 330 is contained within housing 180. Exemplary prime powersources include a standard AC wall outlet. Power supply 152 includes abattery management interface 334 which controls the recharging of thebatteries with battery charger 330.

In one embodiment, power system 152 is recharged by a power source 338of the asset 102. An exemplary power source 338 is a DC generator ofasset 102. Referring to FIG. 8, a controller of asset 102 determines ifasset 102 is operating and stationary (or otherwise operating at a lowpower level), as represented by block 350. The controller checks anoperational sensor 352 to determine if asset 102 is operational.Exemplary operational sensors include engine sensors which indicate theoperation of propulsion devices 108. The controller also checks in thecase of an airplane 102, a wheel down sensor 354, which indicates whenthe landing gear of airplane 102 is lowered. If the controllerdetermines that airplane 102 is stationary (wheels down) andoperational, then the controller provides charging energy to batterycharger 330, as represented by block 356. In one embodiment, airplane102 does not need to be stationary, but rather only be operating at alow power level, such as flying at a moderate speed. In this case, thecontroller monitors a power load of airplane 102 and provides chargingenergy to battery charger 330 when the power load is below a thresholdamount.

Cooling system 156 provides cooling to the other components ofcountermeasure device 100. In one embodiment, cooling system 156provides cooling to laser source module 160. In one embodiment, coolingsystem 156 provides cooling to laser source module 160 and the opticalcomponents of beam control module 162. In one embodiment, cooling system156 provides cooling fluid to power system 152, laser source module 160,and the optical components of beam control module 162. Cooling system156 may be either air-cooled or liquid cooled. Exemplary cooling systemsare provided from Thermo Tek, Inc. located at 1200 Lakeside Parkway,Suite 200 in Flower Mound, Tex.

As indicated in FIG. 1, the components of countermeasure device 100 arecoupled to each other and to asset 102 through a digital communicationsystem. In one embodiment, the digital communication system includes acommon bus for the components within countermeasure device 100. Althougha digital communication system is illustrated, any suitable connectionis acceptable between the components, such as analog connections. In oneembodiment, laser source module 160 is coupled to enable input 143 andfire input 145 through discrete connections outside of the digitalcommunication system. Further, warning/cuing system 130 is coupled tosystem controller 154 through a separate communication connection. Anexemplary communication connection is the MIL-STD-1553 Bus.

Referring to FIG. 9, in one embodiment, countermeasure device 100 alsoincludes a target tracking and beam pointing system 210. Target trackingand beam pointing system 210 monitors the scene surrounding asset 102.In one embodiment, beam pointing system 210 includes a vision system,illustratively a FLIR system 212, which provides images of the scenesurrounding asset 102. FLIR system 212, illustratively, has a separateoptical window 178 through which the vision system monitors the locationof mobile tracking device 110. In one embodiment, FLIR system 212 usesthe same optical window 190 as output beam 176 and is bore sighted tooutput beam 176.

Referring to FIGS. 10A and 10B, an operation of countermeasure device100 is illustrated. Referring to FIG. 10A, a check is made by acontroller 132 of asset 102 whether warning/cuing system 130 is active,as represented by block 360. Further, warning/cuing system 130 is set tosurvey mode, as represented by block 362. In survey mode, warning/cuingsystem 130 monitors the environment around asset 102 to determine if amobile tracking device 110 is approaching asset 102, as represented byblock 364. If a mobile tracking device 110 is detected by warning/cuingsystem 130, then the controller 132 of asset 102 determines thecoordinates of mobile tracking device 110, as represented by block 366.Warning/cuing system 130 may also sound an alarm or provide anotherindication of mobile tracking device 110 to the operator of asset 102.Exemplary coordinates for the case when the asset is airplane 102 arethe azimuth and elevation angles of mobile tracking device 110 relativeto airplane 102.

The controller 132 of asset 102 passes the coordinates of mobiletracking device 110 to countermeasure device 100, as represented byblock 368. Countermeasure device 100 moves rotatable head 184 to thespecified angular position and FLIR system 212 is directed at thespecified coordinates. FLIR system 212 may be gimbaled to moveindependently within housing 180. The controller 132 of asset 102determines if mobile tracking device 110 has acquired mobile trackingdevice 110 with tracking module 210, as represented by block 370. Ifcountermeasure device 100 has not acquired mobile tracking device 110,new coordinates of mobile tracking device 110 are determined and passedagain to countermeasure device 100. As such, countermeasure device 100remains slaved to controller 132. If countermeasure device 100 hasacquired mobile tracking device 110 then the initial coordinatescorresponding to the lock on location of mobile tracking device 110 aresaved by system controller 154, as represented by block 371.

Next, system controller 154 of countermeasure device 100 checks to seeif countermeasure device 100 is authorized to fire continuous wave laser166, as represented by block 372. Continuous wave laser 166 isauthorized to fire when fire input 145 is set to fire. If continuouswave laser 166 is not authorized to fire, then an indication of this isprovided to the operator of countermeasure device 100, as represented byblock 374. Exemplary indications include visual alarms, audio alarms,tactile alarms, and combinations thereof. If continuous wave laser 166is authorized to fire, then continuous wave laser 166 is fired at mobiletracking device 110. Beam control module 162 has already adjusted theoutput direction of collimated beam 176 to coincide with the directionto countermeasure device 100.

After countermeasure device 100 has acquired mobile tracking device 110,beam pointing system 210 tracks the location of mobile tracking device110 and updates the coordinates for mobile tracking device 110, asrepresented by block 379. Beam control module 162 rotates and reflector179 tilts, as necessary, to maintain collimated beam 176 on mobiletracking device 110.

The position of beam control module 162 is monitored to determine whenit has moved a threshold amount, as represented by block 378. Oncemobile tracking device 110 has changed direction by a threshold amount,it no longer is locked on asset 102 and the threat to asset 102 isneutralized. This change in direction of mobile tracking device 110 isindicated by the change in direction of beam control module 162 to keepcollimated beam 176 on mobile tracking device 110. Once the thresholdamount is reached, continuous wave laser 166 is deactivated asrepresented by block 381. Control is again passed back to warning/cuingsystem 130 to monitor for additional mobile tracking devices 110.

In one embodiment, the threshold amount is about 10 degrees in eitherthe azimuth or elevation directions. In one embodiment, the thresholdamount is about 5 degrees in either the azimuth or elevation directions.In one embodiment, the threshold amount is about 3 degrees in either theazimuth or elevation directions. In one embodiment, system controller154 monitors the time since mobile tracking device 110 was acquired bycountermeasure device 100 and deactivates continuous wave laser 166 oncea threshold amount of time has passed.

In one embodiment, beam pointing system 210 has a narrower field of viewthan sensor modules 131 of warning/cuing system 130. As such, sensormodules 131 are able to survey the surrounding environment for mobiletracking device 110 approaching from various directions, while beampointing system 210 is fixed on the narrow portion of the environmentsurrounding a detected mobile tracking device 110.

In one embodiment, warning/cuing system 130 is integrated intocountermeasure device 100 and system controller 154 detects the launchof a mobile tracking device 110 based on the images captured bywarning/cuing system 130. Although various tasks are discussed as beingcarried out by one of warning/cuing system 130, controller 132, andsystem controller 154, these may be carried out by a common controller.

As mentioned herein output beam 176 is produced by a continuous wavelaser 166. Output beam 176 is able to defeat mobile tracking devices 110which modulate the incoming electromagnetic radiation even though outputbeam 176 is not pulsed and contains no jamming code. Output beam 176 isalso effective against imaging detection systems of more advanced mobiletracking device 110.

Referring to FIG. 11, a ship 380 is shown having a rudder 382 andcountermeasure device 100. Also shown is a second ship 384 having arudder 386 which directs the direction of travel of second ship 384.Second ship 384 also incorporates a mobile tracking device 110. Secondship 384 is attempting to track first ship 380 and close the distancebetween first ship 380 and second ship 384. Mobile tracking device 110generates course correction signals for second ship 384 so that secondship 384 continues to close on first ship 380. In this example, mobiletracking device 110 does not include a separate propulsion system 112and guidance system 114. Rather, second ship 384 has its own propulsionsystem, such as an engine, and rudder 386 directs the travel path ofsecond ship 384 based on input from controller 116.

As illustrated in FIG. 3, telescope 120 of mobile tracking device 110attempts to collect a large amount of electromagnet radiation to extendthe viewing range of the countermeasure device 100. The distance dindicated in FIG. 11, corresponds to a viewing distance of mobiletracking device 110 which is the distance at which mobile trackingdevice 110 is first able to detect first ship 380. At distances beyonddistance d, mobile tracking device 110 is not able to see first ship380. Of course, mobile tracking device 110 may be closer to first ship380 than the distance d and in fact over time mobile tracking device 110tracks first ship 380 so that second ship 384 closes the distancebetween second ship 384 and first ship 380.

Countermeasure device 100, upon locking on the position of mobiletracking device 110, fires continuous wave laser 166 such that outputbeam 176 is received by telescope 120 of mobile tracking device 110.Output beam 176 has different effects on mobile tracking device 110depending on the separation of mobile tracking device 110 fromcountermeasure device 100. Distance d is illustratively divided intothree bands, a near distance band 392, a mid distance band 394, and afar distance band 396. At distances in near distance band 392, theenergy of output beam 176 explodes seeker head 115 and destroys mobiletracking device 110. At distances in mid distance band 394, the energyof output beam 176 destroys the functionality of detector 118. In oneexample, a countermeasure device 100 including a 3 kW Yterrbiumcontinuous fiber laser as continuous wave laser 166 destroyed a focalplane array detector of a mobile tracking device 110 at a distance ofabout 3 kilometers.

At distances in far distance band 396, the energy of output beam 176produces a plurality of internal localized sources within mobiletracking device 110. These internal localized sources are produced bythe energy of output beam 176 being absorbed by the optical componentsof mobile tracking device 110 which then reradiate the absorbed energyin multiple wavelengths, similar to a blackbody source. Referring toFIG. 3, six internal localized sources 400 are illustrated. Sources 400Aand 400B correspond to filter 125. Source 400C corresponds to opticalwindow 128. Source 400D corresponds to secondary mirror 123. Source 400Ecorresponds to primary mirror 121. Source 400F corresponds to optics124. The sources 400 may be produced based on the absorptioncharacteristics of the material of each component or the presence of animperfection in a component. For instance, optical window 128 may becomescratched during travel resulting in an imperfection that producessource 400C. Although six sources 400 are illustrated, a single source400 or other number of sources 400 may be produced at various times.

The source 400 produces infrared energy which is brighter than theinfrared signature of asset 102 being tracked by mobile tracking device110. As such, controller 116 of mobile tracking device 110 interpretsthe respective source 400 as asset 102 instead of asset 102 itself. Ifsource 400 is off-axis, this will cause controller 116 to try to centersource 400 resulting in error signal 129 being increased. Guidancesystem 114 will then turn mobile tracking device 110 in an attempt tocenter source 400. This results in mobile tracking device 110 turningaway from the location of asset 102. Since source 400 is radiating froma portion of mobile tracking device 110, it cannot be centered. In oneembodiment, the power level of continuous wave laser 166 is about 3 kWexiting countermeasure device 100.

Source 400 do not explode mobile tracking device 110, such as whathappens in near distance band 392, nor is detector 118 of mobiletracking device 110 destroyed, such as what happens in mid distance band394. Rather, source 400 confuses controller 116 to believe that one ormore (if multiple sources) additional objects are present in the fieldof view of mobile tracking device 110 with a higher intensity than asset102. Controller 116 tracks the brightest object in its field of view andthus attempts to track one of sources 400, instead of asset 102.

In far distance band 396, mobile tracking device 110 is not destroyed,but rather sent off course. As mobile tracking device 110 approachescountermeasure device 100 the power level of output beam 176 increasesexponentially resulting in detector 118 being destroyed in mid distanceband 394 and/or mobile tracking device 110 exploding in near distanceband 392. Of course, if mobile tracking device 110 is engaged in fardistance band 396 mobile tracking device 110 likely will not enter middistance band 394 because mobile tracking device 110 will be directed ina different direction due to output beam 176.

In one embodiment, a wavelength of the continuous wave laser 166 and apower of the continuous wave laser are selected to cause at least one ofan interference effect and a destructive effect to one of the sensor ofthe mobile tracking device and a guidance system of the mobile trackingdevice. In one embodiment, the interference effect is a heat energyabsorption of the continuous wave laser and a re-radiation of energywithin the guidance system of the mobile tracking device. In oneembodiment, the interference effect include at least one of heating andelectromagnetic interference which create an undesired interference withthe sensor or guidance system of the mobile tracking device. In oneembodiment, the destructive effect includes at least one of melting,ablating, fracturing, signal destruction, data transfer destruction,erasure of data, modification of data; unprogrammed signalinputs/outputs from integrated circuits in one of the sensor of themobile tracking device and a guidance system of the mobile trackingdevice.

The effects of sources 400 are shown through a comparison of FIGS. 14and 15 with FIGS. 12 and 13. Referring to FIG. 12, a typical response ofa mobile tracking device 110 in far distance band 396 is shown. Thedegree of turn being carried out by a mobile tracking device 110 isproportional to a voltage associated with a gyroscope of the seeker head115. In FIG. 12, a raw voltage of detector 118 is shown as curve 250.Also shown is the voltage associated with the gyroscope of the seekerhead 115 as curve 252. The amplitude of curve 252 corresponds to errorsignal 129. The curve 252 shown in FIG. 12, represents a mobile trackingdevice 110 which has locked onto an asset 102 and is following directlybehind the asset 102. The Fourier transform of curve 250 is shown inFIG. 13. As shown in FIG. 13, the spectrum 254 for curve 250 isgenerally tightly defined around 1000 Hz. This is generally consistentwith the modulation scheme of the mobile tracking device 110 when it isinline with asset 102.

Referring to FIG. 14, a 3 kilowatt, continuous wave, infrared, Ytterbiumsingle mode fiber laser with an m² of 1 was used as continuous wavelaser 166 of countermeasure device 100 associated with an asset 102. Intests, a mobile tracking device 110 was fired at asset 102.Countermeasure device 100 directed a continuous beam of optical energy176 at the optical window 128 of mobile tracking device 110. Thecontinuous beam of optical energy causes the generation of sources 400which are falsely recognized by mobile tracking device 110 as asset 102.

Referring to FIG. 14, the corresponding curves 250′ and 252′ for theabove example are shown. A first portion 260 of curve 250′ (andcorresponding portion 262 of curve 252′) are shown prior to activationof continuous wave laser 166. As shown by portion 262, the travel ofmobile tracking device 110 is fairly straight. Continuous wave laser 166is activated at point 264. This results in detector 118 being floodedwith IR energy as represented by the increase in amplitude of curve 250′and the generation of sources 400. The generation of sources 400 appearsto be later in time potentially indicating the need for the componentsof mobile tracking device 110 to heat up to cause sources 400. Atportion 264 of curve 252′ controller 116 is instructing guidance system114 to turn mobile tracking device 110 more aggressively. This increasein turning of mobile tracking device 110 increases in portion 266 evenas the intensity of curve 250′ falls in portion 268. This fall inintensity is indicative of mobile tracking device 110 moving far offcourse so that not as much of collimated beam 176 enters optical window128. As shown in FIG. 15, the spectrum 254′ for curve 250′ isconsiderably broadened compared to spectrum 254 of FIG. 12.

Referring to FIG. 16, mobile tracking device 110 is traveling in adirection towards asset 102, as represented by block 410. This isillustrated in FIG. 2A wherein an airborne mobile tracking device 110 isshown traveling in direction 412 towards asset 102. As explained herein,countermeasure device 100 fires continuous wave laser 166 to directoutput beam 176 towards mobile tracking device 110. This causes thegeneration of at least one localized source 400 within mobile trackingdevice 110 which is within a field of view of mobile tracking device110. These one or more localized sources 400 are brighter than theinfrared energy radiated from asset 102 and are generated at locationswhich do not correspond with the current direction 412 of mobiletracking device 110, as represented by block 414 in FIG. 16. As such,controller 116 attempts to point mobile tracking device 110 at thebrighter source 400 and in doing so changes the direction of mobiletracking device 110 to direction 416 as shown in FIG. 2B. Beam controlmodule 162 alters the direction of output beam 176 to coincide with thenew direction of mobile tracking device 110, as represented by block 420in FIG. 16. This again causes the generation of the localized sources400 within mobile tracking device 110 which are within a field of viewof mobile tracking device 110. As such, controller 116 attempts to pointmobile tracking device 110 at the brighter source 400 and in doing sochanges the direction of mobile tracking device 110 to direction 422 asshown in FIG. 2C. Beam control module 162 alters the direction of outputbeam 176 to coincide with the new direction of mobile tracking device110. Once again this causes the generation of the localized sources 400within mobile tracking device 110 which are within a field of view ofmobile tracking device 110. As such, controller 116 attempts to pointmobile tracking device 110 at the brighter source 400 and in doing sochanges the direction of mobile tracking device 110 to direction 424 asshown in FIG. 2D. In moving beam control module 162 to track mobiletracking device 110 along the direction 424, rotatable head 184 exceedsthe threshold rotation amount and continuous wave laser 166 isdeactivated, as shown in FIG. 2D.

Unlike prior art countermeasure devices, countermeasure device 100 isnot mobile tracking device 110 specific. Rather, countermeasure device100 is effective against both imaging and non-imaging mobile trackingdevices 110. Countermeasure device 100 relies on the continuousprovision of optical energy into mobile tracking device 110 to producelocalized sources 400 within the field of view of mobile tracking device110 such that detector 118 is confused as to the location of asset 102.

In another example of the use of countermeasure device 100, a 3 kW,continuous wave, infrared, Ytterbium single mode fiber laser was used ascontinuous wave laser 166 of countermeasure device 100 associated withan asset 102. In tests, a plurality of different mobile infrared mobiletracking devices 110 were fired at asset 102 while asset 102 was atground level. Countermeasure device each time 100 directed output beam176 at the optical window of the respective mobile tracking device 110.The countermeasure device 100 was effective against all of the pluralityof different mobile tracking device 110 at a range of up to about 1250meters from countermeasure device 100. A computer model was made whereinasset 102 was at ground level, a wavelength of continuous wave laser 166was set to 1.07 μm, and values for additional parameters countermeasuredevice 100 and mobile tracking device 110 were set. The computer modelprovided a predicted range of up to 1290 meters for a plurality ofdifferent mobile tracking device 110. This computer model demonstratedgood agreement with the experimentally obtained range of up to 1250meters.

In a further example of the use of countermeasure device 100, a 3kilowatt, continuous wave, infrared, Ytterbium single mode fiber laserwas used as continuous wave laser 166 of countermeasure device 100associated with an asset 102. In tests, a specific mobile trackingdevice 110 was fired at asset 102 while asset 102 was at ground level.Countermeasure device 100 directed output beam 176 at the optical windowof mobile tracking device 110. The countermeasure device 100 waseffective against the specific mobile tracking device 110 at a range ofup to about 2650 meters from countermeasure device 100. Theabove-mentioned computer model provided a predicted range of up to 2440meters for the specific mobile tracking device 110. This demonstratesgood agreement with the experimentally obtained range of up to 2650meters.

Returning to FIG. 9, in one embodiment, beam pointing system 210 furtherincludes a laser designator system 214. Laser designator system 214includes a pulsed laser which is directed at mobile tracking device 110and reflected therefrom. Based on the reflected signal, laser designatorsystem 214 is able to determine a distance from countermeasure device100 to mobile tracking device 110. In the case wherein countermeasuredevice 100 includes focusing optics 177 or wherein beam expander 172 maybe focused, one of system controller 154 and beam pointing system 210adjusts a focal length of focusing optics 177 to focus output beam 176at the location of mobile tracking device 110. In one embodiment, outputbeam 176 is focused at a distance shorter than the determined range tomobile tracking device 110, the distance being chosen based on anestimated speed of mobile tracking device 110. In one embodiment, thisdistance corresponds to the expected position of mobile tracking device110 based on assumptions regarding the relative difference in speedbetween asset 102 and mobile tracking device 110. In one embodiment, theestimated speed of mobile tracking device 110 is selected based on thetype of mobile tracking device 110 which is identified based on aretro-reflection received from mobile tracking device 110.

Laser designator system 214, illustratively, has a separate opticalwindow 215 through which the laser beam of laser designator system 214is sent out of countermeasure device 100 and the reflection from mobiletracking device 110 is received to determine the distance to mobiletracking device 110. In one embodiment, laser designator system 214 usesthe same optical window 190 as output beam 176 and is bore sighted tooutput beam 176.

In one embodiment, continuous laser 166 is replaced with a plurality oflaser sources the output of which are combined by presenting the outputof each proximate the focus of beam expander 172. In one embodiment, afirst output fiber corresponding to a first laser source is surroundedby a plurality of output fibers from a respective plurality of lasersources. The outputs of each of the fibers are incoherently combined toscale the overall laser power to a high level which may be damage ordestroy large targets. In one embodiment, the outputs at the input tobeam expander 172 are positioned to produce a generally Gaussian beam inthe far field of beam expander 172.

While this invention has been described as having an exemplary design,the present invention may be further modified within the spirit andscope of this disclosure. This application is therefore intended tocover any variations, uses, or adaptations of the invention using itsgeneral principles. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains.

1. An apparatus for interacting with a mobile tracking device, theapparatus comprising: a plurality of sensor modules which monitor theenvironment; a first controller portion operatively connected to theplurality of sensor modules, the first controller portion determining apresence of the mobile tracking device in the environment based oninformation collected by the plurality of sensor modules and a currentlocation of the mobile tracking device; a countermeasure systemincluding a second controller portion which receives the currentlocation of the mobile tracking device from the first controllerportion, orients a tracking system of the countermeasure system based onthe current location of the mobile tracking device, detects the mobiletracking device, updates the location of the mobile tracking device,activates a continuous wave laser, and directs a continuous beam ofoptical energy at the mobile tracking device.
 2. The apparatus of claim1, wherein the controller continues to update the current location ofthe mobile tracking device until the countermeasure system detects themobile tracking device, the countermeasure system using the updatedcurrent location to orient the tracking system.
 3. The apparatus ofclaim 2, wherein the plurality of sensor modules have a wide field ofview to survey the environment around the body and the countermeasuresystem has a narrower field of view to focus on the location of themobile tracking device.
 4. The apparatus of claim 1, wherein thecountermeasure system includes a beam control module which controls adirection of the continuous beam of optical energy based on the updatedlocation of the mobile tracking device.
 5. The apparatus of claim 4,wherein the continuous beam of optical energy is provided until the beamcontrol module has caused the direction of the continuous beam ofoptical energy to move by a predetermined threshold amount.
 6. Theapparatus of claim 5, wherein the predetermined threshold amount isthree degrees.
 7. The apparatus of claim 6, wherein the countermeasuresystem includes a housing and beam control module includes a positioningsystem which includes a rotatable head coupled to the housing andincluding an optical window through which the continuous beam of opticalenergy exits counter measure system, the positioning system rotating therotatable head to control the direction of the continuous beam ofoptical energy.
 8. The apparatus of claim 7, wherein the positioningsystem further includes a moveable optical component which may be movedto control the direction of the continuous beam of optical energy. 9.The apparatus of claim 1, wherein the countermeasure system includes abeam control module which controls a direction of the continuous beam ofoptical energy based on the updated location of the mobile trackingdevice, the beam control module being coupled to the continuous wavefiber laser through an optical conduit.
 10. The apparatus of claim 1,wherein the continuous beam of optical energy causes the mobile trackingdevice to explode in a first separation band; causes components of themobile tracking device to become inoperative in a second separationband, the second separation band corresponding to distances longer thanfirst separation band; and causes localized internal sources within theseeker head which cause the mobile tracking device to alter itsdirection of travel away from an asset in a third separation band, thethird separation band corresponding to distances longer than the secondseparation band.
 11. The apparatus of claim 1, wherein the firstcontroller portion corresponds to a first controller and the secondcontroller portion corresponds to a second controller, the secondcontroller being separate from the first controller.
 12. The apparatusof claim 1, wherein a wavelength of the continuous wave laser and apower of the continuous wave laser are selected to cause at least one ofan interference effect and a destructive effect to one of the sensor ofthe mobile tracking device and a guidance system of the mobile trackingdevice.
 13. The apparatus of claim 12, wherein said interference effectis a heat energy absorption of the continuous wave laser and are-radiation of energy within the guidance system of the mobile trackingdevice.
 14. The apparatus of claim 12, wherein said interference effectinclude at least one of heating and electromagnetic interference whichcreate an undesired interference with the sensor or guidance system ofthe mobile tracking device.
 15. The apparatus of claim 12, wherein thedestructive effect includes at least one of melting, ablating,fracturing, signal destruction, data transfer destruction, erasure,modification; unprogrammed signal inputs/outputs from integratedcircuits in one of the sensor of the mobile tracking device and aguidance system of the mobile tracking device.